A cappella (Italian for From the chapel/choir) music is vocal music or singing without instrumental accompaniment, or a piece intended to be performed in this way. A cappella was originally intended to differentiate between Renaissance polyphony and Baroque concertato style. In the 19th century a renewed interest in Renaissance polyphony coupled with an ignorance of the fact that vocal parts were often doubled by instrumentalists led to the term coming to mean unaccompanied vocal music. In modern usage, a cappella often refers to an all-vocal performance of any style, including barbershop, doo wop, and modern pop/rock. Today, a cappella also includes sample/loop "vocal only" productions by producers like Jimmy Spice Curry, Teddy Riley, Wyclef, and others. (source: wikipedia.org)